The Cl– Lewis structure contains one chlorine atom having four lone pairs on it.
Plus, there is a negative (-1) charge on the chlorine atom.
Steps
By using the following steps, you can easily draw the Cl– Lewis structure.
#1 Draw skeleton
#2 Mark lone pairs
#3 Calculate formal charge and check stability (if octet is already completed on central atom)
Let’s one by one discuss each step in detail.
#1 Draw skeleton
In this step, first calculate the total number of valence electrons. And then, decide the central atom.
- Let’s calculate the total number of valence electrons
We know that… chlorine is a group 17 element. Hence, chlorine has seven valence electrons.
Now Cl– has one chlorine atom.
So the total number of valence electrons = valence electrons of chlorine atom
And Cl– has a negative (-1) charge, so we have to add one more electron.
Therefore, the total number of valence electrons = 7 + 1 = 8
- Now decide the central atom
There is only one atom in Cl–. Hence, assume that chlorine is the central atom.
So now, draw the rough skeleton structure for the Cl– Lewis structure something like this:
Also read: How to draw Lewis structure of IBr (4 steps)
#2 Mark lone pairs
As calculated earlier, we have a total of 8 valence electrons.
Two valence electrons represent one lone pair. So eight valence electrons = four lone pairs.
Note that chlorine is a period 3 element, so it can keep more than 8 electrons in its last shell.
Also, make sure that you start marking these lone pairs on outside atoms first. And then, on the central atom.
There is no outside atom. So the central atom (chlorine) will get four lone pairs.
Now draw the Cl– Lewis structure looks something like this:
In the above structure, you can see that the octet is completed on the central atom (chlorine). Therefore, the octet rule is satisfied.
After completing the octet, one last thing we need to do is, calculate the formal charge and check the stability of the above structure.
Also read: How to draw Lewis structure of SbF5 (4 steps)
#3 Calculate formal charge and check stability
The following formula is used to calculate the formal charges on atoms:
Formal charge = valence electrons – nonbonding electrons – ½ bonding electrons
Collect the data from the above structure and then, write it down below as follows:
- For chlorine atom
Valence electrons = 7
Nonbonding electrons = 8
Bonding electrons = 0
Formal charge = 7 – 8 – ½ (0) = -1
Mention the formal charge on the structure. So the Cl– Lewis structure looks something like this:
In the above structure, you can see that the formal charge of chlorine is closer to zero. Therefore, this is the most stable Lewis structure of Cl–.
Now Cl– is an ion having a negative (-1) charge, so draw brackets around the above Lewis structure and mention that charge on the top right corner. And then, the Cl– Lewis structure looks something like this:
Related
- Lewis structure of IBr
- Lewis structure of SbF5
- Lewis structure of C5H12
- Lewis structure of SbCl5
- Lewis structure of CH3SH
External links
- Draw the Lewis dot structure for the chloride ion – Homework.Study.com
- How to draw a Lewis structure of a chloride ion (Cl–)? – Quizlet
- Draw the Lewis structure for Cl and its ion – Chegg
Deep
Rootmemory.com was founded by Deep Rana, who is a mechanical engineer by profession and a blogger by passion. He has a good conceptual knowledge on different educational topics and he provides the same on this website. He loves to learn something new everyday and believes that the best utilization of free time is developing a new skill.